Process

ABSTRACT

Fabrics containing fibers of selected polymers prepared from bis(4-aminocyclohexyl)methane and linear aliphatic dicarboxylic acids, bis(4-isothiocyanatocyclohexyl)methane or bis(4isocyanatocyclohexyl)methane develop improved liveliness upon treatment with chloroform.

United States Patent Williams 1 Mar. 7, 1972 [54] PROCESS [56] Reierences Cited [72] inventor: Meurig W. Williams, Rochester, NY. UNITED STATES PATENTS [73] Assign E- ldu P n de N m r n mp ny, 2,380,003 7/1945 Whitehead ..8/l3l Wilmington, Del. 3,393,210 7/1968 Speck ..260/371 [22] Filed: Apr. 7, 1970 211 Appl. No.: 26,435

Primary Examiner-George F. Lesmes Assistant Examiner-B. Bettis Att0meyS0l Schwartz [57] ABSTRACT Fabrics containing fibers of selected polymers prepared from I bis(4-aminocyclohexyl)methane and linear aliphatic dicarboxylic acids, bis(4-isothiocyanatocyclohexyl)methane or bis(4-isocyanatocyclohexyl)methane develop improved liveliness upon treatment with chloroform.

6 Claims, No Drawings PROCESS BACKGROUND OF THE INVENTION This invention concerns a fabric finishing process for obtaining fabric with increased liveliness. In particular, it concerns treatment of fabrics prepared from defined PACM polymers by treatment with an organic swelling agent.

The PACM polyamides prepared from bis(4-aminocyclohexyl)methane (PACM) and linear aliphatic dicarboxylic acids and copolyamides thereof are described in Speck U.S. Pat. No. 3,393,210, Gadecki & Speck U.S. Pat. No. Reissue 26,614 (originally U.S. Pat. No. 3,249,591) and in Knospe U.S. Pat. No. 3,4l6,302. PACM-S1 is prepared from PACM and bis(4-isothiocyanatocyclohexyl)methane. PACM-1 is prepared from PACM and bis(4-isocyanatocyclohexyl)methane. The fabrics treated in accordance with this invention are prepared from fiber of the foregoing polymers.

British Pat. No. 917,957 discloses treatment of a polyglutamate fabric with a variety of swelling agents including aqueous phenol, chloroform, methylene chloride and trichloroethylene. The treated fabrics are described as softer, livelier, and as having'improved crease recovery and practically no crease marking. British Pat. No. 805,525 indicates that polyesters may be treated with chlorinated hydrocarbon. However, teachings with respect to such nonanalogous materials are of little guidance to one dealing with PACM polymers. For example, the aqueous phenol treatment converts the PACM polyamide fabrics to stiff, boardy materials while methylene chloride has no substantial effect on such fabrics. In fact, British Pat. No. 805,525 suggests that treatment with chlorinated hydrocarbon does not improve polyamide fabrics.

SUMMARY OF THE INVENTION The purpose of the present invention is to provide a process for developing improved liveliness in fabrics prepared from specified PACM yarns without discoloration. The process comprises immersing the fabric in chloroform at a temperature ranging from room temperature up to and including the boiling point of the chloroform, and removing the fabric from the chloroform and drying the fabric.

DETAILS OF THE INVENTION Suitable Fabrics for Treatment While fabrics of PACM yarns are in general amenable to improvement by the chloroform treatment of the invention, excessive prior treatment of the yarn or fabric with heat, strong swelling agents, or with both heat and strong swelling agents should be avoided if improved liveliness is to be obtained by the process of the invention. For example, dilute aqueous pelargonic acid solutions are strong swelling agents for PACM-12 yarn when applied in an autoclave at above 100 C. However, fabrics which have been pretreated with aqueous pelargonic acid (e.g., percent based on weight of fabric) are still useful in the present invention if they have not been treated at temperatures above 100 C. in the aqueous pelargonic swelling agent.

Treatment in Chloroforrn The PACM fabrics may be treated with chloroform at temperatures between room temperature and the boiling point of chloroform. The fabric may be exposed to the chloroform by immersion in a bath. The treatment requires exposure in the bath for only a fewminutes. The fabric may be treated by passing continuously through the bath or by allowing to stand in the bath. The chloroform which is used for the treatment may be diluted with small quantities of other constituents. Preferably no more than 10 percent of diluent is present in the solvent used for the treatment. PACM-S1 fabrics (described in the examples below) are treated preferably at the boiling point of chloroform. Ordinarily, PACM-12 fabrics may be treated at room temperature. If the yarns have been dyed in an autoclave without carrier or are subjected to some other treatment that similarly increases crystallinity, the fabric may require treatment at the boiling point of chloroform. Heatsetting of the fabric at too high a temperature or excessive annealing or heat treatments of the yarn during yarn processing may result in fabrics that do not respond adequately to chloroform treatment even at the boiling point of chloroform.

Drying or Removing the Chloroform from the Fabric After removal of the fabric from the chloroform bath or other exposure, several methods for removing the chloroform from the fabric are available. The fabric may be passed continuously through an oven to volatilize chloroform, or the chloroform may be removed by allowing the fabric to stand in a ventilated hood at room temperature.

Variations of the Process A variety of physical forms of the fiber may be used. The fiber in the fabric may exist as staple or continuous filament. However, the invention is of greater usefulness in the staple field because these highly twisted yarns have not been easily softened by prior art methods.

The fabrics to be treated in accordance with the present invention should be composed of at least 50 percent by weight of fibers of the aforementioned PACM polymers in order to v benefit substantially from the chloroform treatment. The fibers of PACM polymer may consist essentially of polyamides prepared from bis(4-aminocyclohexyl)methane (PACM) of at least 50 percent tt (trans-trans stereoisomer) and linear aliphatic dicarboxylic acids such as azelaic, sebacic, dodecanedioic, tetradecanedioic (the 9-, 10-, 12- and 14- acids, respectively) or mixtures thereof. Other dicarboxylic acids such as isophthalic and terephthalic acids may be substituted for a minor proportion of the linear aliphatic dicarboxylic acids as in PACM-12/PACM-l (/10) representing the product formed from PACM and a mixture of 12- acid and isophthalic acid (90 percent by weight and 10 percent by weight, respectively, of PACM-l2 and PACM-I in the copolymer). Alternatively, the fibers of PACM polymer may consist essentially of polymer prepared from PACM and bis(4-isothiocyanatocyclohexyl)methane or bis(4-isocyanatocyclohexyl)methane. While the fiber may consist of a singlehomogeneous polymer, useful results are also obtained with bicomponent fibers such as fibers containing two polymer components in side-by-side as in Example 111 or sheath core relationship along the length of the fiber, at least one of the components being an aforementioned polymer and being present to the extent of at least 50 percent by weight.

The process of chloroform treatment thus offers a technique for improving the liveliness of fabrics containing fibers (including mixtures of fibers) of the following group: monocomponent fibers of polymer prepared from PACM and a linear aliphatic dicarboxylic acid, preferably a nine to 14 carbon atom saturated acid; monocomponent fibers of polymer prepared from PACM and bis(4-isothiocyanatocyclohexyl)methane; monocomponent fibers of polymer prepared from PACM and bis(4-isocyanatocyclohexyl)methane; and bicomponent fibers wherein one of the aforementioned polymers constitutes at least 50 percent by weight of the bicomponent fiber. Preferably, the fabric to be treated will contain only fibers of the foregoing group, however, greater liveliness can be achieved even with fabrics containing at least 50 percent by weight of such fibers.

The fibers may be precrimped by treatment in a stuffer box or by other bulking operations.

The fabric types which respond to this treatment include worsted staple fabrics, satins, plain weaves, twills and crepes. Since fabrics are frequently treated with heat and chemicals in processing for use in garments, such treatments may affect the susceptibility of the fabrics to processing with chloroform or may change the qualities of the fabric after treatment with chloroform. It is, therefore, important to use care in processing of such fabrics. For example, in aftertreatments it is possible to apply epoxy resins, acrylic resins or polysiloxancs for improved soil resistance, static resistance, handle, slickneiis or wrinkle resistance. The fabric may also be treated with caustic or other chemicals to provide greater susceptibility for these finish applications.

Test Methods and Procedures Liveliness and suppleness of fabrics may be measured by use of bending rigidity and friction moment measurements. Data for these determinations are obtained using a continuous reading moment-curvature measuring instrument described in Textile Research Journal, Aug., 1968, p. 870-873. In this measurement the fabric is bent and unbent with linearly increasing and decreasing curvature. The instrument plots the bending moment (in lb./in.) vs. curvature (inf for a bending and unbending cycle. The bending and unbending curves each have a straight line portion after the initial bending and unbending portions of the curves. The instrument is reversed from bending to unbending when the curvature reaches 3.5 inf. The slope R of the straight line segment of the curve (bending or unbending) is the bending rigidity. The slope R is inversely related to suppleness. A high value for R is indicative of low suppleness, and vice versa. The value R is an experimental value which is related to the theoretical value 2E1, described in the reference.

The straight line portions of the bending and unbending curves are substantially parallel. Half of the distance between the parallel portions of the bending and unbending curves measured parallel to the bending moment axis is the friction moment M (moment of frictional restraint). The ratio of the bending rigidity to the friction moment, R/M relates elastic energy to frictional work loss. It is therefore an indication of liveliness. A high ratio indicates high liveliness. Fabrics with low ratio RIM differ noticeably in their aesthetic appeal from fabrics with high ratio.

EXAMPLE l Cospun yarns were melt spun according to the methods described in Knospe US. Pat. No. 3,416,302. The cospun yarns were composed of filaments of two different compositions. In the cospun yarn 50percent of the filaments were of homopolymer PACM-12 (70 tt) composition, i.e., derived from PACM diamine (containing 70 percent by weight transtrans stereoisomer) and a 12-carbon linear aliphatic dicarboxylic acid (dodecanedioic acid). The remaining 50 percent of the filaments were copolymer designated as PACM- l2/PACM-l (90/10). This copolymer was derived from PACM diamine (70 percent trans-trans) and a mixture of dodecanedioic acid (12) and isophthalic acid (I) to obtain 90 percent by weight and percent by weight of PACM-12 and PACM-l in the copolymer. The cospun yarns were drawn and annealed after the melt-spinning and quenching operation. The filaments were spun from Y-shaped orifices and had a trilobal cross-sectional shape of the type claimed in U.S. Pat. No. 2,939,201. The yarns contained 2 percent by weight aluminum silicate. The homopolymer relative viscosity (7.4 g. of polymer in 100 ml. of a mixture of 50 percent by weight of 98 percent formic acid and 50 percent by weight of phenol) was about 46 and the copolymer relative viscosity was about 50. Yarns of two different deniers were prepared, one batch being about 30 denier and the other about 60 denier. The properties of the two cospun yarns were as follows:

The 30 denier yarn was twisted 20 turns/inch in the Z direction for use in the warp of a fabric. Two ends of the 60 denier yarns were plied together with five turns per inch twist in the 2 direction for use in the filling of the fabric. The yarns were preshrunk (7-10 percent shrinkage) in a steam autoclave at 260 F. for 30 minutes prior to weaving. A fabric was woven from the above yarns using a 8 shaft satin warp face pattern. The greige fabric had 343 ends per inch and 98 picks per inch. Fabric weight was 3.7 oz./yd..

The greige fabric did not possessa large degree of liveliness and suppleness. The fabric was then treated by dipping in a pan containing chloroform at room temperature for 10 minutes in open width relaxed condition. The fabric was then removed and allowed to air dry for 2 hours. Liveliness and suppleness were remarkably improved as indicated by data These numbers indicate that the chloroform treated fabric is more supple (lower R) and livelier (higher R/M;,) than the untreated fabric. Finished fabric construction was 420 ends/inch and 124 picks/inch (higher than greige), and finished fabric weight was 4.8 ore/yd. (higher than greige).

EXAMPLE 11 A PACM-l2 polymer containing 2.0 percent by weight aluminum silicate, 0.12 percent by weight potassium phenyl phosphinate is prepared, having a relative viscosity of 18.5. The relative viscosity was determined using 7.4 g. of polymer in 100 ml. of a mixture of 50 percent by weight of 98 percent formic acid/50 percent by weight of phenol. The meltspinning comprises extrusion at 306 C. at a rate of 7.7 lbs/hr. through a spinneret having 102 orifices having Y-shaped cross sections so as to produce trilobal fibers. The spinning filaments are blanketed at the spinneret with about 1 lb./hr. of superheated steam at 180 C. and quenched with about ftP/min. of 21 C. air. The spinning speed is 800 y.p.m. The resulting yarn, which is wound on a bobbin, has filaments with a spun denier per filament of 7.0, a modification ratio of 2.61, and a relative viscosity of 25.4.

Fifty-four ends of the yarn are simultaneously cold drawn 2.65 X (to 2.65 times original length) at a speed of 100 yards/min. and then allowed to relax 5 percent across a hot plate at C. to form a tow of 14,500 denier. The drawn fiber has a tenacity of 3.25 g.p.d., an elongation of 26.5 percent, a wet shrinkage at 100 C. of 1.76 percent and a denier per filament of 2.64. Six ends of the drawn tow are then combined and crimped in a 2-inch stuffer box crimper to yield an 87,000 denier tow having a crimp level of 23.2 crimps per inch.

The 87,000 denier tow is fed at 104 y.p.m. through an applicator where an aminosiloxane/polyepoxide emulsion is continuously applied. The emulsion is absorbed on the fiber to yield 0.60.8 percent siloxane based on dry fiber weight. The tow is then cut to 3.0-inch staple. The application of the aminosiloxane/polyepoxide emulsion and the cutting are a continuous operation. The staple is heated at 135 C. for 15 minutes in a belt drying oven to effect polymerization of the siloxane on the fiber surface as a slickener.

The 3.0 d.'p.f. trilobal PACM-lZ staple was spun on the worsted system to obtain a 2-ply 60 worsted count (2/60 w.c.). Twist multiplier was 3. The yarn was twist set at F., 80 percent relative humidity for 1 hr.

The above yarn was woven into a plain weave pattern with 58 ends per inch and 46 picks per inch. The fabric was then scoured. Scouring was carried out in two stages. in the first stage the aqueous bath'at 200 F. contained gm./liter Varsol" (a hydrocarbon solvent), 1 gm./liter "Triton X-100 (a nonionic surface-active agent) and 1 gmjliter of tetrasodiumpyrophosphate, a detergent builder. For the second scouring stage the bath contained 0.5 g. Dupanol RA, a surface active agent and 0.5 of tetrasodium-pyrophosphate per liter of water. The bath temperature reached 160 F. The purpose of this second scouring step was to remove residual Varsol (hydrocarbon solvent) used in the first step.

The fabric was passed over a vacuum slot to facilitate drying. At this stage the fabric had a harsh, dead hand. The partially dried fabric was then loosely wrapped in open width form on a perforated 17-inch wide beam and dipped into a stainless steel tank containing chloroform at room temperature for 5 minutes. The beam was then removed from the tank. The fabric was unroiled and looped over a series of rolls (open width) to facilitate air drying. The fabric was then heat-set in open width (on a laboratory pin frame restraint in two directions) for 2 minutes at 356 F. The resultant fabric was noticeably more supple and livelier than before the chloroform treatment.

A second fabric was made identically to the above except that the chloroform treatment was omitted. The resulting fabric was noticeably less lively and supple than the chloroform-treated fabric.

EXAMPLE Ill A yarn composed of 68 round bicomponent fibers is prepared by melt spinning. Two different polymers (PACM- 12 and a random copolymer PACM-12/PACM-l 90/ [0) are fed to each spinneret hole and the flows are adjusted so that half of each fiber is composed of each of these polymers. Each polymer contains 2.0 percent by weight aluminum silicate. The PACM diamine used in the two polymers is 70 percent trans-trans stereoisomer. Spinning block and spinneret are both maintained at 300 C.

The yarn is drawn 3X at 165 C., the windup roll speed being 1,519 yards/min. The yarn has a total denier of 260 (3.8 d.p.f.). The yarn is cut to a 4-inch staple length and is stufferbox crimped to yield 12-15 mechanical crimps per inch. N0 surface modifier is applied.

The staple is spun on the worsted system to obtain a l-ply 30 worsted count 1/30 w.c. Twist multiplier is 3. Twist is set at 180 F., 80 percent relative humidity for 1 hour. The staple yarn is woven into a plain weave pattern with 56 ends per inch and 50 picks per inch.

The fabric is finished identically to that in Example 11 except that after the scouring step (and before chloroform treatment) the fabric is dried at 250 F. in a Fametex pin tenter frame at a speed of 6.5 yards per minute. Otherwise the finishing is as before and includes scouring, chloroform treatment, carrier dyeing with pelargonic acid, and heat setting again at 180 C. The fabric before chloroform treatment is relatively stiff and dead. Following chloroform treatment the fabric has a lively, supple handle. These aesthetic features are substantially retained throughout the subsequent finishing operations.

EXAMPLE IV The staple used in this fabric was a 50/50 blend by weight of trilobal homofibers with composition as described in Example 11 and round bicomponent fibers with composition as described in Example 111.

Spinning of the 3.5 d.p.f. homofiber in a manner analogous to Example 11 gives the following yarn properties:

Denier per filament 3.5; tenacity 3.10 g.p.d.;

elongation at break 26.4 percent.

The tow was cut to 3.0-inch staple length with application of surface modifier as described in Example 11.

The bicomponent yarn was prepared by feeding two different polymers to each spinneret hole as described in Example 111. The draw ratio was again 3X. Properties of the bicomponent yarns were:

Denier per filament= 5.1; tenacity 2.59 g.p.d.;

elongation at break 28.4 percent; and initial modulus 29.8 g.p.d. The yarn was cut to a 4-inch staple length, mechanically crimped, and the emulsion surface modifier was applied as indicated in Example 11, at 1.0 percent based on dry fiber weight and heated.

The two different staple fibers were blended together in a 50/50 weight ratio on a worsted system card The above staple was spun using the worsted system to a one ply 30 worsted count (1/30 w.c.) with a 16 turns/inch Z twist (twist multiplier 3) and twist set at 180 F., percent relative humidity for 1 hr.

The yarn was woven in a plain weave pattern. Loom construction was 60 ends/inch X 50 picks/inch. The fabric after weaving was scoured in a jig to remove loom finishes and accumulated dirt, as in Example 11 using this time two scourings with Varsol hydrocarbons at 200 F. and a subsequent scour without Varsol hydrocarbons at F.

Before drying, however, the fabric (about 2,170 g.) was treated in the jig with a butyl benzoate dispersion comprising 200 liters of water and sufficient butyl benzoate to provide 10 percent based on fiber weight. Butyl benzoate is a known dye carrier for use in PACM-polyamide. It is a swelling agent for PACM polyamide fibers. The bath containing the butyl benzoate was heated to 212 F. This carrier treatment was added to the finishing sequence because it was found that it yielded fabrics that were firmer and more desirable aesthetically for certain enduses such as mens slacks. Before the fabric was removed from the jig it was scoured in a fresh bath at 180 F. to remove residual butyl benzoate. The fabric was rinsed and then dried at 250 F. at 10 yards per minute on a Fametex pin tenter.

The fabric was then chloroform treated as per Example 11 except that it was heat set 2 minutes at 356 F. on a Fametex pin tenter instead of on a laboratory pin frame. The fabric was supple and lively.

EXAMPLE V Measured properties of the fabric described in Example IV after the three scourings and prior to carrier and chloroform treatments were as follows:

Ends/inch 66 Picks/inch 58 Fabric wt. oz./yd. 4.2

Warp Fill Bending rigidity 142 138 Friction moment 112 122 Bending rigiditylfrict. 1.27 1.13

moment A portion of the triple-scoured fabric was treated in chloroform without subjecting first to the butyl benzoate treatment. This piece of fabric was dipped into a stainless steel pan containing chloroform at room temperature for 30 minutes (open width, relaxed) and then allowed to air dry (relaxed). The resulting fabric was remarkably livelier and more supple than before exposure to chloroform. After the treatment fabric properties were as follows:

Ends/inch 76 Picks/inch 68 Fabric weight oz.lyd.' 6.0

Warp Filling Bending rigidity 43.5 48.8 Friction moment 9.7 8.5 Bending rigiditylfrict. 4.59 5.17

moment EXAMPLE Vl This example illustrates the treatment of fabric of PACM- Sl, a polythiourea which is prepared by the reaction between bis(4-aminocyclohexyl)methane (PACM) and bis(4-isothiocyanatocyclohexyl)methane.

To a stirred solution of PACM (154.4 g., 0.735 mole, 70 percent trans-trans) in 4,500 ml. of N,N-dimethylacetamide is added, under nitrogen, bis(4-isothiocyanatocyclohexyl)methane (216.1 g., 0.735 mole, 70 percent trans-trans). Complete solution occurs within a few minutes and the temperature of the reaction mixture rises to 50 C. After 5 minutes, an 8 percent solution of LiCl in N,N-dimethylacetamide (900 ml.) is added. The reaction mixture is allowed to polymerize overnight at ambient temperature. The reaction mixture contains 6.2 percent by weight polymer and 1.24 percent by weight LiCl.

The viscous, clear reaction mixture is extruded into a 65 C. water bath through a 60-hole spinneret. A yarn is obtained which has an inherent viscosity of 1.1 (measured in m-cresol solution containing 0.5 g. of polymer in 100 ml. of solution at 30 C.). The extruded yarn is subsequently drawn to 1.3 times its original length (1.3X) by passage through a hot tube (5 ft. long) filled with nitrogen at 225 C.

A plain weave fabric is prepared from the continuous multifilament yarn. The fabric has the following construction: warp 12 turns per inch Z, 84 ends per inch; filling 12 turns per inch Z, 80 picks per inch. The greige fabric is dead in feel. The fabric is then given a relaxed treatment in boiling chloroform for minutes, after which it is dried in air and ironed. A very lively white fabric (without discoloration) is then obtained. It shrank 13 percent in the warp and 10 percent in the filling. For comparison a greige fabric is heat set (relaxed) at 250 C. for 4 minutes. It becomes very lively but is discolored by the treatment (cream colored).

EXAMPLE VII A staple fabric of PACM-SI polymer was prepared using the method of polymerization and spinning of Example V1. The concentration of initial ingredients was adjusted to give 8.5 percent polymer in the N,N-dirnethylacetamide solution prior to spinning. The solution also contained 1.8 percent lithium chloride. The solution was extruded into water at 30 C. using a 580-hole spinneret, each hole being 0.003 inch in diameter. The yarn was continuously withdrawn from the bath and wound up at 30 to 52 ft./min. The inherent viscosity of polymer in the yarn was 1.2 in m-cresol. The yarn denier was 2,550. This yarn was drawn 1.3X in a hot tube (5 ft. long) containing nitrogen at 230 C. The yarn was crimped by passage through a gear crimper at 200 C. at 7 ft./minute. Pressure was applied by a 442 g. weight.

The crimped yarn was cut into 4-inch long staple and this staple was spun into yarn on the worsted system whereby a singles worsted count of 40 was obtained. This yarn had 16 turns/inch Z twist. It was two-plied then with 12 turns/inch S twist to give 2/40 w.c. This yarn was woven into a 2X2 twill fabric. The construction on the loom was 60 ends/inch and 40 picks/inch. The fabric was scoured in a 2 percent aqueous solution of a surface-active agent. The scoured fabric was soft and dead.

The scoured fabric was treated in chloroform at the boil for 5 minutes. After drying at room temperature and ironing the fabric was again evaluated. It was soft and lively.

EXAMPLE VIII A PACM-l polymer was prepared by reaction of 70 percent u bis(4-aminocyclohexyl)methane with 70 percent tt bis(4- isocyanatocyclohexyl)methane. The polymer had an inherent viscosity of 1.73 in m-cresol. A yarn was dry spun from this polymer and then drawn 1.7X at 270 C. The yarn was 83 denier and had 30 filaments. The drawn filament properties were as follows:

Denier per filament 2.7 Tenacity, gpd. 3.5 Elongation, I: 24

Initial modulus gpd.

A taffeta fabric was prepared from the drawn 83 denier yarn after twisting l2 turns/inch.

The fabric on the loom contained 84 ends/inch and picks/inch.

A portion of the fabric was finished by first scouring onehalf hour in 0.5 percent aqueous surface-active agent solution, drying and ironing. A limp white fabric resulted. Shrinkage upon scour was 6.6 percent in the warp and 5 percent in the fill direction. The fabric was boiled open width in chloroform for 10 minutes, dried in air, and heat-set relaxed 60 seconds at 230 C. Total shrinkage (based on greige fabric) was 16 percent in the warp and 13 percent in the fill direction. No dimenv EXAMPLE IX Fabrics from a wide variety of PACM polymer fibers are useful in the invention. Fibers with a high degree of swelling in chloroform are expected to be more susceptible to improve ment by chloroform treatment in fabrics. Illustrative of suitable fibers are those described in Table 4 below. The polymer types in the table are indicated by listing of PACM diamine and acid precursor. For brevity the acid constituent is indicated by a number. This number indicates the number of carbon atoms per molecule in a linear dicarboxylic aliphatic acid wherein the two carboxyl groups occupy the terminal position of a straight carbon chain. In the table percent tr indicates percent by weight of the trans-trans stereoisomer in the diamine. The last two items in the table have been indicated by formula for brevity. The bicomponent fiber contains two different polymeric compositions arranged in contiguous adhering fashion along the length of the fiber. One composition is PACM-l2 homopolymer. The other composition is a copolymer prepared from PACM diamine, 12-acid, and isophthalic acid. The PACM constituent is 70 percent trans-trans. The copolymer contains percent by weight PACM-l2 and 10 percent by weight PACM-l. The last fiber in the table is a single component fiber prepared from copolymer of the type used in the bicomponent fiber.

TABLE 4 Polymer Derived From Diamine acid bis( 4-amino-2-methyl cyclohexyUmethane l2 bis(4-amino-2-rnethyl cyclohexyhmethane 10 bis( 4-amino-3-methyl eyclohexynrncthane l0 bis(4-amino'3-methyl cyclchexyUmethane bis(4-aminocyclohexyl)methane (70%) 9 bis(4-aminoeyclohexyl)methane (70%) bis(4-aminocyclohexyl)methane (70%") bis(4-aminocyclohexyl)methane (70%) Bicomponent PACMJZIIPACM-lZ/PACM-l 90/10 10%") PACM-lZ/PACM-l (90110 mean What is claimed is:

l. A process for developing improved liveliness in fabrics comprising 1. selecting a fabric containing at least 50 percent by weight of fibers of the following group: fibers that consist essentially of polymer prepared from A. bis(4-aminocyclohexyl)methane and linear aliphatic dicarboxylic acid, B. bis(4-aminocyclohexyl)methane and bis(4-isothiocyanatocyclohexyl)methane, or C. bis(4-aminocyclohexyl)methane and bis(4-isocyanatocyclohexyl )methane, bicomponent fibers wherein a polymer prepared from A), B) or C) constitutes at least 50 percent by weight of the bicomponent fiber, and blends of at least two such different fibers,

2. immersing the fabric in chloroform at a temperature ranging from room temperature up to and including the boiling point of the chloroform,

3. removing the fabric from the chloroform and 4. drying the fabric.

2. The process of claim 1 wherein the fabric to be treated contains at least 50 percent by weight of fibers that consist essentially of polymer prepared from bis(4-aminocyclohexyl) methane and dodecanedioic acid.

3. The process of claim 1 wherein the fabric to be treated contains at least 50 percent by weight of a blend of l) fibers that consist essentially of polymer prepared from bis(4-aminocyclohexyl)methane and dodecanedioic acid and 2) bicomponent fibers wherein the polymer prepared from bis(4- aminocyclohexyl)methane and dodecanedioic acid constitutes at least 50 percent by weight.

4. The process of claim 1 wherein the fabric to be treated contains at least 50 percent by weight of fibers that consist essentially of polymer prepared from bis(4-aminocyclohexyl)methane and bis(4-isothiocyanatocyclohexyl)methane.

5. The process of claim 1 wherein the fabric to be treated contains at least 50 percent by weight of fibers that consist essentially of polymer prepared from bis(4-aminocyclohexyl)methane and bis(4-isocyanatocyclohexyl)methane.

6. A process for developing improved liveliness in fabrics comprising selecting a fabric containing at least 50 percent by weight of a blend of (1) fibers that consist essentially of polymer prepared from bis(4-aminocyclohexyl) methane and dodecanedioic acid, and (2) fibers that consist essentially of polymer prepared from bis(4-aminocyclohexyl)methane and a mixture of dodecanedioic and isophthalic acids, immersing the fabric in chloroform at a temperature ranging from room temperature up to and including the boiling point of the chloroform, removing the fabric from the chloroform and drying the fabric. 

2. The process of claim 1 wherein the fabric to be treated contains at least 50 percent by weight of fibers that consist essentially of polymer prepared from bis(4-aminocyclohexyl) methane and dodecanedioic acid.
 2. immersing the fabric in chloroform at a temperature ranging from room temperature up to and including the boiling point of the chloroform,
 3. removing the fabric from the chloroform and
 3. The process of claim 1 wherein the fabric to be treated contains at least 50 percent by weight of a blend of 1) fibers that consist essentially of polymer prepared from bis(4-aminocyclohexyl)methane and dodecanedioic acid and 2) bicomponent fibers wherein the polymer prepared from bis(4-aminocyclohexyl)methane and dodecanedioic acid constitutes at least 50 percent by weight.
 4. The process of claim 1 wherein the fabric to be treated contains at least 50 percent by weight of fibers that consist essentially of polymer prepared from bis(4-aminocyclohexyl)methane and bis(4-isothiocyanatocyclohexyl)methane.
 4. drying the fabric.
 5. The process of claim 1 wherein the fabric to be treated contains at least 50 percent by weight of fibers that consist essentially of polymer prepared from bis(4-aminocyclohexyl)methane and bis(4-isocyanatocyclohexyl)methane.
 6. A process for developing improved liveliness in fabrics comprising selecting a fabric containing at least 50 percent by weight of a blend of (1) fibers that consist essentially of polymer prepared from bis(4-aminocyclohexyl) methane and dodecanedioic acid, and (2) fibers that consist essentially of polymer prepared from bis(4-aminocyclohexyl)methane and a mixture of dodecanedioic and isophthalic acids, immersing the fabric in chloroform at a temperature ranging from room temperature up to and including the boiling point of the chloroform, removing the fabric from the chloroform and drying the fabric. 